625 research outputs found

    Retirees Look Back on the Years

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    Professors Howard Leichter, Linda Olds and Kareen Sturgeon share memories of their years at Linfield

    Torque-dependent remodeling of the bacterial flagellar motor

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    Multisubunit protein complexes are ubiquitous in biology and perform a plethora of essential functions. Most of the scientific literature treats such assemblies as static: their function is assumed to be independent of their manner of assembly, and their structure is assumed to remain intact until they are degraded. Recent observations of the bacterial flagellar motor, among others, bring these notions into question. The torque-generating stator units of the motor assemble and disassemble in response to changes in load. Here, we used electrorotation to drive tethered cells forward, which decreases motor load, and measured the resulting stator dynamics. No disassembly occurred while the torque remained high, but all of the stator units were released when the motor was spun near the zero-torque speed. When the electrorotation was turned off, so that the load was again high, stator units were recruited, increasing motor speed in a stepwise fashion. A model in which speed affects the binding rate and torque affects the free energy of bound stator units captures the observed torque-dependent stator assembly dynamics, providing a quantitative framework for the environmentally regulated self-assembly of a major macromolecular machine

    Data Census of a Geographically-Bounded Tweet Set to Enhance Common Operational Picture Tools

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    Location information is of particular importance to crisis informatics. The Twitter API provides several methods to assess a rough location and/or the speciïŹc latitude and longitude in which a post originated. This paper offers a comparison of location information provided by Twitter’s four geolocation methods. The study aggregates one month of data from the greater Cincinnati, Ohio metropolitan area and assesses the relative contribution that each method can make to common operational picture tools used by crisis informatics researchers. Results show that of 49,744 Tweets, 4% contained geotags, 85.2% contained a location in the users’ proïŹle, and 3.5% contained no apparent location data, but were gathered using the bounding box method and would not have been identiïŹed using traditional methods of gathering data using geotagged Tweets or user proïŹle information alone. We reïŹ‚ect on these results in light of design implications for common operational picture tools (COPs)

    Bridging the gap between instructional design and double loop learning

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    Spoelstra, H., Matera, M., Rusman, E., Van Bruggen, J., & Koper, R. (2006). Bridging the gap between instructional design and double loop learning. Proceedings of IV International Conference on Multimedia and Information and Communication Technologies in Education (m-ICTE2006). November, 22-25, 2006, Seville, Spain.There seems to be a gap between instructional design, as implemented in workflow-like e-learning sys-tems, and double loop learning, because the former predefines educational processes and the latter as-sumes these processes can be reflected upon and can be modified by the learners. Instructional designs implemented in workflow-like e-learning systems that use modelling standards enable portability of the designs. While maintaining this advantage of portability, the COOPER environment aims to make room for learning reflection and influence as well. We will present a pedagogical scenario called “Virtual Com-pany”, which uses double loop learning extensively, to demonstrate the feasibility of our proposed solu-tion. We provide learners with “atomic actions”, that can be used to create and revise processes “on the fly”, thus enabling double-loop learning.This article is sponsored by the COOPER Project that is funded by the European Commission's 6th Framework Programme, priority 2 IST. Contract no.: 027073 (www.cooper-project.org

    Building Information Modelling – Experts® Views on Standardisation and Industry Deployment

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    The goal of the single building information model has existed for at least thirty years and various standards have been published leading up to the ten-year development of the Industry Foundation Classes. These have been initiatives from researchers, software developers and standards committees. Now large property owners are becoming aware of the benefits of moving IT tools from specific applications towards more comprehensive solutions. This study addresses the state of Building Information Models and the conditions necessary for them to become more widely used. It is a qualitative study based on information from a number of international experts and has asked a series of questions about the feasibility of BIMs, the conditions necessary for their success, and the role of standards with particular reference to the IFCs. Some key statements were distilled from the diverse answers received and indicate that BIM solutions appear too complex for many and may need to be applied in limited areas initially. Standards are generally supported but not applied rigorously and a range of these are relevant to BIM. Benefits will depend upon the building procurement methods used and there should be special roles within the project team to manage information. Case studies are starting to appear and these could be used for publicity. The IFCs are rather oversold and their complexities should be hidden within simple-to-use software. Inevitably major questions remain and property owners may be the key to answering some of these. A framework for presenting standards, backed up by case studies of successful projects, is the solution proposed to provide better information on where particular BIM standards and solutions should be applied in building projects

    Use of Standards for CAD Layers in Building

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    One of the central issues in making efficient use of IT in the design, construction and maintenance of buildings is the sharing of the digital building data across disciplines and lifecycle stages. One technology which enables data sharing is CAD layering, which to be of real use requires the definition of standards. This paper focuses on the background, objectives and effectiveness of the International standard ISO 13567, Organisation and naming of layers for CAD. In particular the efficiency and effectiveness of the standardisation and standard implementation process are in focus, rather than the technical details. The study was conducted as a qualitative study with a number of experts who responded to a semi-structured mail questionnaire, supplemented by personal interviews. The main results were that CAD layer standards based on the ISO standard have been implemented, particularly in northern European countries, but are not very widely used. A major problem which was identified was the lack of resources for marketing and implementing the standard as national variations, once it had been formally accepted

    Problem Specification for FY12 Modeling of UNF During Extended Storage

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    The Nuclear Energy Advanced Modeling and Simulation (NEAMS) program of the Advanced Modeling and Simulation Office (AMSO) of the US Department of Energy, Office of Nuclear Energy (DOE/NE) has invested in the initial extension and application of advanced nuclear simulation tools to address relevant needs in evaluating the performance of used nuclear fuel (UNF) during extended periods of dry storage. There are many significant challenges associated with the prediction of the behavior of used fuel during extended periods of dry storage and subsequent transportation. The initial activities are focused on integrating with the Used Fuel Disposition (UFD) Campaign of the DOE/NE and a demonstration that the Advanced Multi-Physics (AMP) Nuclear Fuel Performance code (AMPFuel) for modeling the mechanical state of the cladding after decades of storage. This initial focus will model the long-term storage of the UNF and account for the effect, and generation, of radially and circumferentially oriented hydride precipitates within the cladding and predict the end of storage (EOS) mechanical state (stress, strain) of the cladding. Predicting the EOS state of the cladding is significant because it (1) provides an estimate of the margin to failure of the cladding during nominal storage operation and it (2) establishes the initial state of the fuel for post-storage transportation. Because there are significant uncertainties associated with the storage conditions, hydride precipitate formation, and the beginning of storage (BOS) condition of the UNF, this will also allow for the development of a rigorous capability to evaluate the relative sensitivities of the uncertainties and can help to guide the experimental and analysis efforts of the UFD Campaign. This document is focused on specifying the problem that will be solved with AMPFuel. An associated report, documents the specifics of the constitutive model that will be developed and implemented in AMPFuel to account for the presence and predict the generation of the hydride precipitates. This report satisfies the deliverable for the DOE Office of Nuclear Energy, Advanced Modeling and Simulation Office, milestone M3MS-12OR0605083, 'Definition of Problem Specification,' which defines the problem to be solved that will satisfy milestone M2MS-12OR0605081, 'Demonstration of the Advanced Multi-Physics (AMP) Nuclear Fuel Performance code for modeling UFD.' This document should provide sufficient detail to model a high burnup pressurized water reactor (PWR) fuel rod to provide an estimate of the end of storage (EOS) mechanical state of the cladding. The fuel rod and irradiation history are based on seven cycles of irradiation in the CP and L H.B. Robinson nuclear reactor, which achieved a discharge burnup of 66.682 MWd/kgU. The fuel has been experimentally examined for storage conditions by Argonne National Laboratory for the NRC. In addition, we have compiled a list of key factors that have been shown to strongly influence the EOS state of the fuel and have identified baseline values and ranges of uncertainties that will be considered. The simulations that will be performed have been described in detail and include the modeling assumptions and boundary conditions

    Parsnips in ELT: stepping out of the comfort zone (Vol. 2)

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    The PARSNIP is, as many of you will know, a reference to all those topics that are commonly left out of the standard ELT coursebook: Politics, Alcohol, Religion, Sex, Narcotics, -Isms, Pork. And it is easy to understand why these things are not included - in simple terms coursebooks are written for the largest possible market and therefore can only ever concentrate on the safest common denominator in terms of topics. You might be able to get away with a discussion on the differences between democratic governments and dictatorships in Portugal, but the chances are you might find it more difficult in Belarus. So if you want to sell a coursebook in both Portugal and Belarus, you have to make sure that the topics are not going to prove overly contentious or possibly lead to the arrest and deportation of the teacher and closing of the school. The result though, is what Mario Rinvolucri described as ““the soft, fudgey, sub-journalistic, woman’s magaziney world of EFLese course materials” - endless worthy discussions about the environment, the role of technology in life and how to have a healthy lifestyle. The Parsnips in ELT project is an attempt to provide resources and support for teachers who do want to engage their classes in more meaningful topics and discussions. Or at the very least to do something different! It is however, up to you and your own personal and professional judgment whether you choose to use these lesson plans in your context and with your classes, or even if you choose to read them at all! Inevitably, there will be some lessons that you will feel are inappropriate to use and some that you feel will really get the class engaged in the topic and the discussion

    The Role of Liver Fibrosis Assessment in the Management of Patients with Chronic Hepatitis B Infection: Lessons Learned from a Single Centre Experience

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    Background & Aims. Assess the clinical utility of the Prati criteria and normal ALT (<40 IU/L) in a cohort of patients with chronic hepatitis B infection (CHB). Methods. Serology, radiology, and histology were obtained in 140 patients with CHB. Results. HBeAg+ group: 7 patients (7/56−12% HBeAg+ group) misclassified as “immunotolerant”, with HBV DNA > 6 log copies/ml and normal ALT, who in fact had moderate/severe fibrosis on liver biopsy. HBeAg− group: 10 patients with normal ALT and moderate/severe fibrosis on liver biopsy; 4 of these patients had >3 log copies/ml HBV DNA levels and 6 patients misclassified as “inactive carriers” with negative HBV DNA levels normal ALT and moderate/severe fibrosis (6/84−7% HBeAg− group). Two male HBeAg+ and three male HBeAg− patients with ALT between 20 and 30 IU/L and moderate/severe fibrosis on liver biopsy would have been further mischaracterised using the Prati criteria for normal ALT. Age and ethnic group were more important predictors of moderate/severe fibrosis in multivariate analysis. Conclusion. HBeAg status, age, ethnic origin with longitudinal assessment of LFTs and viral load should be studied in patients with “normal ALT” at the upper end of normal range (ALT 20–40 IU/L) to appropriately classify patients and identify patients for liver fibrosis assessment to inform treatment decisions
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